Mickey,
Spoke to one of our educators/counselor/HIV testers about your question and this is the response that I got:
Many needles, when they are new, will make a popping sound. We actually tried it with a new needle just a few minutes ago, and there was no popping sound, so the answer would be that all new needles DO NOT make that sound.
However, you may notice that the first time you pull back the plunger, it feels tight. Every time after that, the plunger is much more loose. Once again, this is not a foolproof message, but can be used as an indicator.
I am very serious when I say, if you think that you have been exposed to ANYTHING (HIV, Hepatitus, etc.), you should be tested. Believe me, I know how scary that can be but I can put you win touch with many good testing centers, including ours, if you are in NY/Hudson Valley Area. The test is free and confidential. I have been tested myself and was very nervous beforehand. I am HIV - and everything else negative, and knew that I probably was, but I wasn't sure.
If you have any questions about the stuff this guy is selling you, you should seriously think about changing dealers. I know you are in the middle of a cycle and don't want to mess up your routine, but you could mess up your life/dreams and future, if you are not extremely careful.
Post me with any questions and I will do my best to get you answers.
Stay safe man!!